极近距离煤层回采巷道合理位置确定与支护技术
Rational Location and Support Technology of Mining Gateway in Seam with Ultra Closed Distance to Above Seam
-
摘要: 基于极近距离下煤层复合顶板回采巷道压力大、巷道维护困难、翻修率高的问题,提出了下煤层回采巷道采用内错布置形式,确定了不同层间距极近距离下煤层回采巷道的分段支护、联合支护方案以及支护参数。结果表明:下煤层回采巷道内错5.0 m布置在低应力区,当煤层顶板厚1.8~4.0 m,采用锚杆+钢带进行一次支护,工字钢棚进行二次支护的联合支护;当顶板上部为实体煤或是采空区且层间距4.0~6.5 m,采用锚杆+钢带进行一次支护,锚索+工字钢梁进行二次支护的联合支护;当顶板厚6.5 m以上或上覆为实体煤时,采用锚杆-钢带进行一次支护,锚索进行二次支护的联合支护效果较为理想。Abstract: Based on the maintenance difficultyt and high repair rate problems of the high pressurized mining gateway with a complex roof in a seam with ultra close d distance to the above seam,the paper proposed that the mining gateway in the below seam should have an internal offset layout.The sectional support,combined supp ort plan and support parameters of the mining gateway in the below seam with an ultra closed distance for different layer distance were determined.The results showed the mining gateway in the below seam would be internally offset located in a low stress zone.When the thickness of the seam roof was 1.84.0 m,the bolt+steel band was applied as the first support and the anchor+H steel beam applied as the second combined support of the roof.When the top of the roof was solid coal or goaf with a dist ance of 4.0 6.5 m,the bolt + steel band would be applied as the first support and the anchor + H steel beam would be applied as the second combined support.When the roof thickness was over 6.5 m or the top of the roof was solid coal,the bolt + steel band would be applied as the first support and the anchor would be applied to the sec ond combined support with a rational support effect.